The completion of the genomic sequences of a number of prokaryotic and eukaryotic species has catalyzed new research approaches to study the structure, function and control of biological processes. They are characterized by the systematic, and in many cases, quantitative analysis of all the molecules of a particular type expressed by a cell or tissue. The systematic analysis of proteins has been termed "proteomics." In an initial phase, most of the proteomics efforts were focused on large-scale protein identification. More recently, the objectives and technologies of proteomics have been diversified and expanded. Current proteomics research attempts to systematically and, where applicable, quantitatively determine the many properties of proteins that determine both their biological function and how different proteins interact to control and execute complex biological processes. Specific properties investigated include protein abundance, state of modification, specific activity, interaction with other biomolecules, half-life, subcellular location and structure. Significant current challenges include the development of suitable technologies to determine these properties on a proteome-wide scale, the interpreation of the large amounts of data obtained, and the integration of different types of data into a coherent model describing a biological process. The goal of the meeting is to bring together the leading experts from the different areas of proteomics research to discuss emerging technologies and their applications to biological and clinical research.